PB1276 - ECMO Platelet Dysfunction and the Quandary of Evaluating Treatment with rvWFC in a Prospective Ex-vivo Approach: A Testability Predicament

Tuesday, June 25, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Presenting Author(s)

MB

Mirjam Bachler

Senior Scientist
Institute for Sports Medicine, Alpine Medicine and Health Tourism (ISAG), UMIT TIROL - Private University For Health Sciences and Health Technology, Austria
Hall in Tirol, Tirol, Austria

Co-Author(s)

PL

Philipp Lichtenberger

Resident physician
Department of Anesthesia and Intensive Care, Medical University Innsbruck, Austria
Innsbruck, Tirol, Austria
LS

Lukas Schausberger

Resident physician
Department of Anesthesia and Intensive Care, Medical University Innsbruck, Austria
Innsbruck, Tirol, Austria
DF

Dietmar Fries

Senior ward physician
Department of Anesthesia and Intensive Care, Medical University Innsbruck, Austria
Innsbruck, Tirol, Austria
EP

Eva-Maria Pfanner-Matijevic

Medical student
Department of Anesthesia and Intensive Care, Medical University Innsbruck, Austria
Innsbruck, Tirol, Austria
SF

Stefan Fleckl

Medical student
Department of Anesthesia and Intensive Care, Medical University Innsbruck, Austria
Innsbruck, Tirol, Austria
MR

Michael Rauscher

Medical student
Department of Anesthesia and Intensive Care, Medical University Innsbruck, Austria
Innsbruck, Tirol, Austria
JB

Johannes Bösch

Resident physician
Department of Anesthesia and Intensive Care, Medical University Innsbruck, Austria
Innsbruck, Tirol, Austria

Background: Apart from the primary disease, bleeding is a leading cause of morbidity and mortality in patients on Extracorporeal Membrane Oxygenation (ECMO), stemming from impaired primary hemostasis due to platelet dysfunction and acquired-von-Willebrand-syndrome (avWS).

Aims: Given the essential role of von-Willebrand-factor (vWF) in platelet adhesion and aggregation, the administration of von-Willebrand-factor-concentrate (vWFC) holds the potential to not only treat avWS but also to improve platelet function.

Methods: Blood samples from eight healthy donors and 20 ECMO-patients were tested. Primary hemostasis and platelet function were evaluated using PFA-100 (Siemens Healthineers) and Multiplate-Analyzer (Roche Diagnostics) measurements of blood samples either untreated or spiked with recombinant vWFC (rvWFC, Vonicog alfa, Takeda Pharmaceutical), equivalent to 80 IU/kg body weight.

Results: In healthy donors, rvWFC significantly improved platelet function, as measured by Multiplate RISTO-test (p=0.0499), although not seen in TRAP-test (p=0.7794) or COL-test (p=0.0929). PFA-100 measurements showed a trend of improvement in the COL/EPI-assay (p=0.0679) and COL/ADP-assay (p=0.0679).

Compared to healthy, platelet dysfunction was present in ECMO-patients, but no improvement in function by rvWFC was observed in any of the tests (p>0.05), probably due to unmet preconditions for reliable results. Only two out of 20 ECMO-patients had a hematocrit above 0.35 L/L, and 11 had a platelet count >100 G/L. Indeed, when analyzing samples from patients with platelets >100 G/L only, there was a significant improvement in the PFA-100 COL/EPI-assay (p=0.0357).

But even without meeting analytic preconditions, ECMO-patients experiencing prolonged measurements or sample depletion in PFA-100 COL/EPI- and COL/ADP-assays significantly decreased (p=0.0159 and p=0.0269) with rvWFC.

Conclusion(s): Impaired primary hemostasis, including platelet dysfunction, is evident in ECMO-patients, and subgroup analyses suggest improvement by treatment with rvWFC. Since preconditions for testing are not met in many ECMO-patients, the administration of vWFC remains a pure clinical decision not supported by any laboratory test or point-of-care monitoring device, such as Multiplate-Analyzer or PFA-100.